DETROIT—Waymo LLC, the self-driving-car unit of Alphabet Inc., has created its own sensor package, suggesting the technology company sees itself supplying both the software and hardware required for autonomous vehicles.

The announcement on Sunday at the start of the North American International Auto Show here gives the clearest window yet into how Waymo might put its self-driving-car project into auto makers’ fleets. Bundling the hardware with the software required for self-driving technology would create an all-in-one package,...